CN116646474A - Lithium metal anode for electrochemical cells and method for making same - Google Patents

Lithium metal anode for electrochemical cells and method for making same Download PDF

Info

Publication number
CN116646474A
CN116646474A CN202211269467.7A CN202211269467A CN116646474A CN 116646474 A CN116646474 A CN 116646474A CN 202211269467 A CN202211269467 A CN 202211269467A CN 116646474 A CN116646474 A CN 116646474A
Authority
CN
China
Prior art keywords
equal
less
pits
lithium
electrochemical layer
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
CN202211269467.7A
Other languages
Chinese (zh)
Inventor
C·里斯
毛崚
A·C·博贝尔
J·D·凯恩
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
GM Global Technology Operations LLC
Original Assignee
GM Global Technology Operations LLC
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by GM Global Technology Operations LLC filed Critical GM Global Technology Operations LLC
Publication of CN116646474A publication Critical patent/CN116646474A/en
Pending legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M4/13—Electrodes for accumulators with non-aqueous electrolyte, e.g. for lithium-accumulators; Processes of manufacture thereof
    • H01M4/134—Electrodes based on metals, Si or alloys
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M10/00—Secondary cells; Manufacture thereof
    • H01M10/05—Accumulators with non-aqueous electrolyte
    • H01M10/052—Li-accumulators
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M10/00—Secondary cells; Manufacture thereof
    • H01M10/05—Accumulators with non-aqueous electrolyte
    • H01M10/052—Li-accumulators
    • H01M10/0525—Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M4/04—Processes of manufacture in general
    • H01M4/043—Processes of manufacture in general involving compressing or compaction
    • H01M4/0435—Rolling or calendering
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M4/04—Processes of manufacture in general
    • H01M4/0438—Processes of manufacture in general by electrochemical processing
    • H01M4/044—Activating, forming or electrochemical attack of the supporting material
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M4/04—Processes of manufacture in general
    • H01M4/049—Manufacturing of an active layer by chemical means
    • H01M4/0492—Chemical attack of the support material
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M4/13—Electrodes for accumulators with non-aqueous electrolyte, e.g. for lithium-accumulators; Processes of manufacture thereof
    • H01M4/139—Processes of manufacture
    • H01M4/1395—Processes of manufacture of electrodes based on metals, Si or alloys
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M10/00—Secondary cells; Manufacture thereof
    • H01M10/05—Accumulators with non-aqueous electrolyte
    • H01M10/058—Construction or manufacture
    • H01M10/0585—Construction or manufacture of accumulators having only flat construction elements, i.e. flat positive electrodes, flat negative electrodes and flat separators
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M2004/021—Physical characteristics, e.g. porosity, surface area
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M2004/026—Electrodes composed of, or comprising, active material characterised by the polarity
    • H01M2004/027—Negative electrodes
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M2004/026—Electrodes composed of, or comprising, active material characterised by the polarity
    • H01M2004/028—Positive electrodes
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M4/36—Selection of substances as active materials, active masses, active liquids
    • H01M4/38—Selection of substances as active materials, active masses, active liquids of elements or alloys
    • H01M4/381—Alkaline or alkaline earth metals elements
    • H01M4/382—Lithium
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
    • Y02E60/10—Energy storage using batteries

Landscapes

  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • General Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Electrochemistry (AREA)
  • Manufacturing & Machinery (AREA)
  • Materials Engineering (AREA)
  • Battery Electrode And Active Subsutance (AREA)

Abstract

The invention discloses a lithium metal anode for an electrochemical cell and a method for preparing the same. An electrode is provided that includes an electrochemical layer defining a surface having a plurality of pits formed thereon. The pits have an average lateral dimension of greater than or equal to about 100 nm to less than or equal to about 100 μm, and an average depth of greater than or equal to about 100 nm to less than or equal to about 50 μm. In certain variations, the pits are formed in situ by applying a current to the electrochemical layer. In other variations, the pits are formed by moving a roller having a plurality of shapes defined thereon along one or more surfaces of the electrochemical layer. In yet another variation, the pits are formed by contacting one or more surfaces of the electrochemical layer with a chemical etchant.

Description

Lithium metal anode for electrochemical cells and method for making same
Technical Field
An electrode for use in an electrochemical cell for circulating lithium ions and a method of forming an electrode for use in an electrochemical cell for circulating lithium ions are disclosed.
Background
This section provides background information related to the present disclosure, which is not necessarily prior art.
Advanced energy storage devices and systems are needed to meet energy and/or power specifications for various products, including automotive products, such as start-stop systems (e.g., 12V start-stop systems), battery assist systems, hybrid electric vehicles ("HEVs"), and electric vehicles ("EVs"). A typical lithium ion battery includes at least two electrodes and an electrolyte and/or separator. One of the two electrodes may function as a positive electrode or cathode and the other electrode may function as a negative electrode or anode. A separator and/or electrolyte may be disposed between the negative electrode and the positive electrode. The electrolyte is adapted to conduct lithium ions between the electrodes and, like the two electrodes, may be in solid and/or liquid form and/or mixtures thereof. In the case of a solid state battery including a solid state electrode and a solid state electrolyte, the solid state electrolyte may physically isolate the electrodes such that no significant separator is required.
The battery pack is configured to reversibly power an associated load device. For example, electrical power may be supplied by the battery pack to the load device until the lithium content of the negative electrode (i.e., cathode) is effectively depleted. The battery can then be recharged by applying a suitable direct current in the opposite direction between the electrodes. More specifically, during discharge, the negative electrode contains a relatively high concentration of deposited or plated lithium, which can be oxidized to lithium ions and electrons. Lithium ions may travel from the negative electrode to the positive electrode (i.e., anode) through a (ion conducting) electrolyte solution contained, for example, within the pores of the interposed separator. Once so far, lithium ions can be incorporated into the positive electrode electroactive material by electrochemical reduction reactions. When lithium ions travel from the negative electrode to the positive electrode, electrons may pass from the negative electrode to the positive electrode through an external circuit.
In contrast, during recharging, the intercalated lithium in the positive electrode may be oxidized to lithium ions and electrons, and the lithium ions travel from the positive electrode to the negative electrode, e.g., through the (ion-conductive) electrolyte through the separator, and the electrons pass through an external circuit to the negative electrode. Once so far, lithium ions may be reduced to elemental lithium in the negative electrode and stored for future use. The battery pack may be recharged by an external power source after any partial or complete discharge of its available capacity. As noted, recharging can reverse the electrochemical reactions that occur during discharge.
During various discharge and recharging processes, for example, due to degradation of active materials (e.g., negative electrodes, positive electrodes, and electrolytes), undesirable metal plating and dendrite formation often occur, thereby producing unusable or dead lithium. The metal dendrites may form protrusions that potentially pierce the separator and cause, for example, internal shorts, which can lead to low coulombic efficiency, poor cycling performance, and potential safety issues. Accordingly, it would be desirable to develop materials for high energy lithium ion batteries that reduce metal dendrite formation and also inhibit or minimize the effects thereof.
Disclosure of Invention
This section provides a general summary of the disclosure, and is not a comprehensive disclosure of its full scope or all of its features.
The present disclosure relates to electrochemical cells including lithium metal electrodes having a predetermined surface design for preferential lithium nucleation during cell operation, and methods of making and using the same.
In various aspects, the present disclosure provides an electrode for use in an electrochemical cell that circulates lithium ions. The electrode may include an electrochemical layer defining a surface having a plurality of pits. The electrochemical layer may comprise lithium metal. The pits of the plurality of pits may have an average lateral dimension of greater than or equal to about 100 nm to less than or equal to about 100 μm, and an average depth of greater than or equal to about 100 nm to less than or equal to about 50 μm.
In one aspect, the pits of the plurality of pits may occupy greater than or equal to about 20% to less than or equal to about 90% of the total surface area of the one or more surfaces.
In one aspect, the pits of the plurality of pits may be randomly distributed over one or more surfaces of the electrochemical layer.
In one aspect, the pits of the plurality of pits may be dispersed at a uniform density over one or more surfaces of the electrochemical layer.
In one aspect, the pits of the plurality of pits may define one or more patterns along one or more surfaces of the electrochemical layer.
In various aspects, the present disclosure provides a method of forming an electrode for use in an electrochemical cell that circulates lithium ions. The method may include forming a plurality of pits on one or more surfaces of a precursor electrochemical layer to form the electrochemical layer. The pits of the plurality of pits may have an average lateral dimension of greater than or equal to about 100 nm to less than or equal to about 100 μm, and a depth of greater than or equal to about 100 nm to less than or equal to about 50 μm. The electrochemical layer may comprise lithium. The electrode may include an electrochemical layer.
In one aspect, forming can include applying greater than or equal to about 0.1 mA/cm to the precursor electrochemical layer 2 To less than or equal to about 10 mA/cm 2 Is used for the current density of the battery. The current density may be applied for a time period of greater than or equal to about 1 second to less than or equal to about 20 minutes.
In one aspect, the method may further comprise assembling a battery, wherein the battery comprises a precursor electrochemical layer.
In one aspect, forming can include moving a roller having a plurality of shapes defined thereon along one or more surfaces of the precursor electrochemical layer.
In one aspect, the method may further comprise assembling a battery, wherein the battery comprises the electrode.
In one aspect, forming can include contacting one or more surfaces of the precursor electrochemical layer with a chemical etchant. The precursor electrochemical layer may be contacted with the chemical etchant for a time period of greater than or equal to about 2 seconds to less than or equal to about 10 minutes.
In one aspect, the chemical etchant may be selected from: diethyl ketone, dodecylbenzene sulfonic acid (DBSA), rosin acid, nitric acid, acetic acid, hydrofluoric acid, sulfuric acid, hydrochloric acid, and combinations thereof.
In one aspect, contacting can include immersing the precursor electrochemical layer in a bath comprising a chemical etchant.
In one aspect, contacting may include spraying one or more surfaces of the precursor electrochemical layer with a solution comprising a chemical etchant.
In one aspect, the method may further comprise assembling a battery, wherein the battery comprises the electrode.
In one aspect, the method may further comprise subjecting the precursor electrochemically (layer) to a grain refinement process.
In various aspects, the present disclosure provides a method of forming a portion of an electrode for use in an electrochemical cell that circulates lithium ions. The method may include forming a plurality of pits on one or more surfaces of the lithium metal film to form an electrode. The pits of the plurality of pits may have an average lateral dimension of greater than or equal to about 100 nm to less than or equal to about 100 μm, and a depth of greater than or equal to about 100 nm to less than or equal to about 50 μm.
In one aspect, the pits of the plurality of pits may be formed in situ by applying a current to the lithium metal film. The current density of the current may be greater than or equal to about 0.1 mA/cm 2 To less than or equal to about 10 mA/cm 2 . The current density may be applied for a time period of greater than or equal to about 1 second to less than or equal to about 20 minutes.
In one aspect, forming can include moving a roller having a plurality of shapes defined thereon along one or more surfaces of the precursor electrochemical layer.
In one aspect, forming can include contacting one or more surfaces of the precursor electrochemical layer with a chemical etchant. The precursor electrochemical layer may be contacted with the chemical etchant for a time period of greater than or equal to about 2 seconds to less than or equal to about 10 minutes.
The invention discloses the following embodiments:
scheme 1. An electrode for use in an electrochemical cell for cycling lithium ions, the electrode comprising:
an electrochemical layer comprising lithium metal and defining a surface defining a plurality of pits having an average lateral dimension of greater than or equal to about 100 nm to less than or equal to about 100 μιη and an average depth of greater than or equal to about 100 nm to less than or equal to about 50 μιη.
The electrode of embodiment 1, wherein the pits of the plurality of pits occupy greater than or equal to about 20% to less than or equal to about 90% of the total surface area of the one or more surfaces.
The negative electrode of embodiment 1, wherein the pits of the plurality of pits are randomly distributed on one or more surfaces of the electrochemical layer.
The electrode of embodiment 1, wherein the pits of the plurality of pits are dispersed at a uniform density on one or more surfaces of the electrochemical layer.
The electrode of embodiment 1, wherein the pits of the plurality of pits define one or more patterns along one or more surfaces of the electrochemical layer.
Scheme 6. A method of forming an electrode for use in an electrochemical cell for circulating lithium ions, the method comprising:
forming a plurality of pits on one or more surfaces of a precursor electrochemical layer to form an electrochemical layer, the electrochemical layer comprising lithium metal, and pits of the plurality of pits having an average lateral dimension of greater than or equal to about 100 nm to less than or equal to about 100 μm, and a depth of greater than or equal to about 100 nm to less than or equal to about 50 μm, wherein the electrode comprises the electrochemical layer.
Scheme 7. The method of embodiment 6 wherein the forming comprises:
applying greater than or equal to about 0.1 mA/cm 2 To less than or equal to about 10 mA/cm 2 Wherein the current density is applied for a time period of from greater than or equal to about 1 second to less than or equal to about 20 minutes.
Scheme 8. The method of embodiment 7, the method further comprising:
a battery comprising the precursor electrochemical layer is assembled.
Scheme 9. The method of embodiment 6 wherein the forming comprises:
a roller having a plurality of shapes defined thereon is moved along one or more surfaces of the precursor electrochemical layer.
Scheme 10. The method according to embodiment 9, the method further comprising:
a battery including the electrodes is assembled.
Scheme 11. The method of embodiment 6 wherein the forming comprises:
contacting one or more surfaces of the precursor electrochemical layer with a chemical etchant, wherein the precursor electrochemical layer is contacted with the chemical etchant for a time period of greater than or equal to about 2 seconds to less than or equal to about 10 minutes.
Scheme 12. The method of embodiment 11 wherein the chemical etchant is selected from the group consisting of: diethyl ketone, dodecylbenzene sulfonic acid (DBSA), rosin acid, nitric acid, acetic acid, hydrofluoric acid, sulfuric acid, hydrochloric acid, and combinations thereof.
Scheme 13. The method of embodiment 11 wherein the contacting comprises:
the precursor electrochemical layer is immersed in a bath containing the chemical etchant.
Scheme 14. The method of embodiment 11 wherein the contacting comprises:
one or more surfaces of the precursor electrochemical layer are sprayed with a solution comprising the chemical etchant.
Scheme 15. The method of embodiment 11, further comprising:
a battery including the electrodes is assembled.
Scheme 16. The method of embodiment 6, further comprising:
the precursor is subjected to a grain refinement process electrochemically (layer).
Scheme 17. A method of forming an electrode for use in an electrochemical cell for circulating lithium ions, the method comprising:
a plurality of pits are formed on one or more surfaces of the lithium metal film to form a portion of the electrode, wherein the pits of the plurality of pits have an average lateral dimension of greater than or equal to about 100 nm to less than or equal to about 100 μιη, and a depth of greater than or equal to about 100 nm to less than or equal to about 50 μιη.
The method of embodiment 17, wherein the pits of the plurality of pits are formed in situ by applying a current to the lithium metal film, wherein the current has a current density of greater than or equal to about 0.1 mA/cm 2 To less than or equal to about 10 mA/cm 2 And applying the current density for a time of greater than or equal to about 1 second to less than or equal to about 20 minutes.
The method of embodiment 18, wherein the forming comprises:
a roller having a plurality of shapes defined thereon is moved along one or more surfaces of the precursor electrochemical layer.
The method of embodiment 19, wherein the forming comprises:
contacting one or more surfaces of the precursor electrochemical layer with a chemical etchant, wherein the precursor electrochemical layer is contacted with the chemical etchant for a time period of greater than or equal to about 2 seconds to less than or equal to about 10 minutes.
Further areas of applicability will become apparent from the description provided herein. The description and specific examples in this summary are intended for purposes of illustration only and are not intended to limit the scope of the present disclosure.
Drawings
The drawings described herein are for illustrative purposes only of selected embodiments and not all possible embodiments and are not intended to limit the scope of the present disclosure.
FIG. 1 is a diagram of an exemplary electrochemical battery cell including a lithium metal negative electrode having a predetermined surface design defined by a plurality of dimples, in accordance with aspects of the present disclosure;
FIG. 2 is a diagram of an exemplary lithium metal negative electrode having a predetermined surface design defined by a plurality of dimples in accordance with aspects of the present disclosure;
FIG. 3 is a flow chart illustrating an exemplary method for forming a lithium metal negative electrode having a predetermined surface design defined by a plurality of dimples in accordance with aspects of the present disclosure;
FIG. 4A is a microscopic image of a lithium metal negative electrode having a predetermined surface design defined by a plurality of dimples, e.g., prepared using the method shown in FIG. 3, in accordance with aspects of the present disclosure;
FIG. 4B is a microscopic image of another lithium metal negative electrode having a predetermined surface design defined by a plurality of dimples, e.g., prepared using the method shown in FIG. 3, in accordance with aspects of the present invention
FIG. 4C is a microscopic image of a lithium metal negative electrode;
FIG. 5 is an illustration of another exemplary method for forming a lithium metal negative electrode having a predetermined surface design defined by a plurality of dimples in accordance with aspects of the present disclosure;
FIG. 6 is a flow chart illustrating another exemplary method for forming a lithium metal negative electrode having a predetermined surface design defined by a plurality of dimples in accordance with aspects of the present disclosure;
fig. 7 is a graph illustrating a discharge capacity retention rate (%) of an exemplary battery pack prepared according to aspects of the present disclosure.
Corresponding reference characters indicate corresponding components throughout the several views of the drawings.
Detailed Description
The exemplary embodiments are provided so that this disclosure will be thorough and will fully convey the scope to those skilled in the art. Numerous specific details are set forth, such as examples of specific compositions, assemblies, devices, and methods, in order to provide a thorough understanding of embodiments of the present disclosure. It will be apparent to one skilled in the art that the exemplary embodiments may be embodied in many different forms without the use of specific details, and that neither should be construed to limit the scope of the disclosure. In some exemplary embodiments, well-known methods, well-known device structures, and well-known techniques have not been described in detail.
The terminology used herein is for the purpose of describing particular example embodiments only and is not intended to be limiting. As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. The terms "comprises," "comprising," "including," and "having" are inclusive and therefore specify the presence of stated features, elements, compositions, steps, integers, operations, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof. Although the open-ended terms "comprising" should be understood to be non-limiting terms used to describe and claim the various embodiments described herein, in certain aspects, the terms may be understood to alternatively be more limiting and restrictive terms, such as "consisting of … …" or "consisting essentially of … …". Thus, for any given embodiment reciting a composition, material, component, element, feature, integer, operation, and/or method step, the disclosure also specifically includes embodiments consisting of, or consisting essentially of, such recited composition, material, component, element, feature, integer, operation, and/or method step. In the case of "consisting of … …," alternative embodiments exclude any additional compositions, materials, components, elements, features, integers, operations, and/or method steps, and in the case of "consisting essentially of … …," any additional compositions, materials, components, elements, features, integers, operations, and/or method steps that substantially affect the essential and novel characteristics are excluded from such embodiments, but are not included in the embodiments.
Any method steps, processes, and operations described herein should not be construed as necessarily requiring their performance in the particular order discussed or illustrated, unless specifically identified as being performed in a performance order. It is also to be understood that additional or alternative steps may be employed unless stated otherwise.
When a component, element, or layer is referred to as being "on," "engaged with," "connected to," or "coupled to" another element, or layer, it can be directly on, engaged with, connected to, or coupled to the other component, element, or layer, or intervening elements or layers may be present. In contrast, when an element is referred to as being "directly on," "directly engaged with," "directly connected to" or "directly coupled to" another element or layer, there may be no intervening elements or layers present. Other words used to describe the relationship between elements should be interpreted in a similar fashion (e.g., "between …" relative "directly between …", "adjacent" relative "directly adjacent", etc.). As used herein, the term "and/or" includes any and all combinations of one or more of the associated Luo Liexiang.
Although the terms first, second, third, etc. may be used herein to describe various steps, elements, components, regions, layers and/or sections, these steps, elements, components, regions, layers and/or sections should not be limited by these terms unless otherwise specified. These terms may be only used to distinguish one step, element, component, region, layer or section from another step, element, component, region, layer or section. Terms such as "first," "second," and other numerical terms when used herein do not imply a sequence or order unless clearly indicated by the context. Thus, a first step, element, component, region, layer or section discussed below could be termed a second step, element, component, region, layer or section without departing from the teachings of the example embodiments.
Spatially or temporally relative terms, such as "before," "after," "inner," "outer," "lower," "upper," and the like, may be used herein for ease of description to describe one element or feature's relationship to another element(s) or feature(s) as illustrated in the figures. In addition to the orientations shown in the drawings, spatially or temporally relative terms may be intended to encompass different orientations of the device or system in use or operation.
Throughout this disclosure, numerical values represent approximate measured values or range limits to encompass slight deviations from the given values and embodiments having approximately the values noted, as well as embodiments having exactly the values noted. Except in the operating examples provided last, all numerical values of parameters (e.g., amounts or conditions) in this specification (including the appended claims) should be construed as modified in all cases by the term "about", whether or not "about" actually appears before the numerical value. "about" means that the recited value allows some slight imprecision (with some approximation of the exact value for this value; approximating this value approximately or reasonably; nearly). If the imprecision provided by "about" is otherwise not otherwise understood in the art with this ordinary meaning, then "about" as used herein refers to at least the deviations that may be caused by ordinary methods of measuring and using such parameters. For example, "about" may include deviations of less than or equal to 5%, optionally less than or equal to 4%, optionally less than or equal to 3%, optionally less than or equal to 2%, optionally less than or equal to 1%, optionally less than or equal to 0.5%, and in some aspects optionally less than or equal to 0.1%.
Moreover, the disclosure of a range includes disclosure of all values and further sub-ranges within the entire range, including disclosure of endpoints and subranges given for the range.
Exemplary embodiments will now be described more fully with reference to the accompanying drawings.
A typical lithium-ion battery includes a first electrode (e.g., positive electrode or cathode) opposite a second electrode (e.g., negative electrode or anode) and a separator and/or electrolyte disposed therebetween. Typically, in lithium-ion battery packs (battery packs), the battery packs (batteries) or cells (cells) may be electrically connected in a stacked or rolled configuration to increase the overall output. The lithium-ion battery operates by reversibly transferring lithium ions between the first and second electrodes. For example, lithium ions may move from a positive electrode to a negative electrode during battery charging and in the opposite direction when the battery is discharging. The electrolyte is suitable for conducting lithium ions and may be in liquid, gel or solid form. For example, an exemplary and schematic illustration of an electrochemical cell (also referred to as a battery) 20 is shown in fig. 1.
Such batteries are used in vehicle or automobile transportation applications (e.g., motorcycles, boats, tractors, buses, motorcycles, mobile homes, camping vehicles, and tanks). However, the present technology may be used in a wide variety of other industries and applications, including aerospace components, consumer goods, devices, buildings (e.g., houses, offices, sheds, and warehouses), office equipment and furniture, as well as industrial equipment machinery, agricultural or farm equipment, or heavy machinery, as non-limiting examples. Further, while the illustrated example includes a single positive electrode cathode and a single anode, those skilled in the art will recognize that the present teachings extend to a variety of other configurations, including those having: one or more cathodes and one or more anodes, and various current collectors employing electroactive layers disposed on or adjacent to one or more surfaces of the current collector.
The battery pack 20 includes a negative electrode 22 (e.g., anode), a positive electrode 24 (e.g., cathode), and a separator 26 disposed between the two electrodes 22, 24. The separator 26 provides electrical isolation between the electrodes 22, 24-preventing physical contact between the electrodes 22, 24. The separator 26 also provides a minimum resistive path for lithium ions (and in some cases, related anions) to pass internally during lithium ion cycling. In various aspects, the separator 26 includes an electrolyte 30, which may also be present in the negative electrode 22 and the positive electrode 24 in certain aspects. In certain variations, the separator 26 may be formed of a solid electrolyte or a semi-solid electrolyte (e.g., a gel electrolyte). For example, the separator 26 may be defined by a plurality of solid electrolyte particles (not shown). In the case of a solid state battery and/or a semi-solid state battery, positive electrode 24 and/or negative electrode 22 may include a plurality of solid state electrolyte particles (not shown). The plurality of solid electrolyte particles included in separator 26 or defining separator 26 may be the same as or different from the plurality of solid electrolyte particles included in positive electrode 24 and/or negative electrode 22.
A first current collector 32 (e.g., a negative electrode current collector) may be located at or near the negative electrode 22. The first current collector 32 may be a metal foil, a metal grid or mesh, or a porous metal comprising copper or any other suitable conductive material known to those skilled in the art. A second current collector 34 (e.g., positive electrode current collector) may be located at or near positive electrode 24. The second current collector 34 may be a metal foil, a metal grid or mesh, or a porous metal comprising aluminum or any other suitable conductive material known to those skilled in the art. The first current collector 32 and the second current collector 34 may collect and move free electrons to the external circuit 40 and collect and move free electrons from the external circuit 40, respectively. For example, an external circuit 40 and a load device 42 that may be interrupted may connect the negative electrode 22 (via the first current collector 32) and the positive electrode 24 (via the second current collector 34).
The battery pack 20 may generate an electrical current during discharge through a reversible electrochemical reaction that occurs when the external circuit 40 is closed (to connect the negative electrode 22 and the positive electrode 24) and the negative electrode 22 has a lower potential than the positive electrode. The chemical potential difference between positive electrode 24 and negative electrode 22 drives electrons generated by reactions at negative electrode 22, such as oxidation of lithium metal, through external circuit 40 toward positive electrode 24. Lithium ions also generated at the negative electrode 22 are simultaneously transferred to the positive electrode 24 through the electrolyte 30 contained in the separator 26. Electrons flow through the external circuit 40 and lithium ions migrate through the separator 26 containing the electrolyte 30, forming intercalated lithium at the positive electrode 24. As described above, electrolyte 30 is also typically present in negative electrode 22 and positive electrode 24. The current flowing through the external circuit 40 may be utilized and directed through the load device 42 until the lithium in the negative electrode 22 is depleted and the capacity of the battery pack 20 is reduced.
By connecting an external power source to the lithium-ion battery pack 20 to reverse the electrochemical reactions that occur during discharge of the battery pack, the battery pack 20 can be charged or re-energized at any time. Connecting an external power source to the battery pack 20 promotes reactions at the positive electrode 24, such as non-spontaneous oxidation of the intercalated lithium, so that electrons and lithium ions are generated. Lithium ions flow back through electrolyte 30 through separator 26 toward negative electrode 22, replenishing negative electrode 22 with lithium (e.g., deposited lithium metal) for use during the next battery discharge event. Thus, a full charge event is considered to be a cycle after a full discharge event, wherein lithium ions circulate between positive electrode 24 and negative electrode 22. The external power source that may be used to charge the battery pack 20 may vary depending on the size, configuration, and particular end use of the battery pack 20. Some notable and exemplary external power sources include, but are not limited to, AC-DC converters and motor vehicle alternators that are connected to an AC power grid through a wall outlet.
In many lithium ion battery constructions, the first current collector 32, the negative electrode 22, the separator 26, the positive electrode 24, and the second current collector 34 are each prepared as relatively thin layers (e.g., from a few microns to a fraction of a millimeter or less in thickness) and are mounted in layers connected in an electrically parallel arrangement to provide suitable electrical energy and power packaging. In various aspects, the battery pack 20 may also include various other components, which, although not shown herein, are known to those of skill in the art. For example, the battery pack 20 may include a housing, a gasket, a terminal cover, tabs, battery terminals, and any other conventional components or materials that may be located within the battery pack 20 (including between or around the negative electrode 22, the positive electrode 24, and/or the separator 26). The battery 20 shown in fig. 1 includes a liquid electrolyte 30 and shows a typical concept of battery operation. However, the present technology is also applicable to solid state batteries and/or semi-solid state batteries comprising solid state electrolytes and/or solid state electrolyte particles and/or semi-solid electrolytes and/or solid state electroactive particles, which may have different designs known to those skilled in the art.
As noted above, the size and shape of the battery pack 20 may vary depending on the particular application for which it is designed. For example, battery powered vehicles and handheld consumer electronic devices are two examples in which the battery pack 20 will most likely be designed for different sizes, capacities and power output specifications. The battery pack 20 may also be connected in series or parallel with other similar lithium ion batteries or battery packs to produce greater voltage output, energy, and power if desired by the load device 42. Thus, the battery pack 20 may generate a current to the load device 42 as part of the external circuit 40. When the battery pack 20 is discharged, the load device 42 may be powered by current through the external circuit 40. While the electrical load device 42 may be any number of known electrical devices, several specific examples include motors for electric vehicles, laptop computers, tablet computers, cellular telephones, and cordless power tools or appliances. The load device 42 may also be an electricity-generating device that charges the battery pack 20 for the purpose of storing electrical energy.
Referring again to fig. 1, positive electrode 24, negative electrode 22, and separator 26 may each include an electrolyte solution or system 30 within their pores that is capable of conducting lithium ions between negative electrode 22 and positive electrode 24. Any suitable electrolyte 30, whether in solid, liquid, or gel form, capable of conducting lithium ions between the negative electrode 22 and the positive electrode 24 may be used in the lithium-ion battery 20. For example, in certain aspects, the electrolyte 30 may be a non-aqueous liquid electrolyte solution (e.g., > 1M) comprising a lithium salt dissolved in an organic solvent or mixture of organic solvents. Many conventional nonaqueous liquid electrolytes 30 may be employed in the battery 20.
Non-limiting examples of lithium salts that can be dissolved in an organic solvent to form a nonaqueous liquid electrolyte solution include lithium hexafluorophosphate (LiPF 6 ) Lithium perchlorate (LiClO) 4 ) Lithium tetrachloroaluminate (LiAlCl) 4 ) Lithium iodide (LiI), lithium bromide (LiBr), lithium thiocyanate (LiSCN), lithium tetrafluoroborate (LiBF) 4 ) Lithium tetraphenyl borate (LiB (C) 6 H 5 ) 4 ) Lithium bis (oxalato) borate (LiB (C) 2 O 4 ) 2 ) (LiBOB), lithium difluorooxalato borate (LiBF) 2 (C 2 O 4 ) Lithium hexafluoroarsenate (LiAsF) 6 ) Lithium trifluoromethane sulfonate (LiCF) 3 SO 3 ) Lithium bis (trifluoromethane) sulfonyl imide (LiN (CF) 3 SO 2 ) 2 ) Lithium bis (fluorosulfonyl) imide (LiN (FSO) 2 ) 2 ) (LiSFI), lithium bis (trifluoromethanesulfonyl) imide (LiTFSI), and combinations thereof. These and other similar lithium salts can be dissolved in various nonaqueous aprotic organic solvents including, but not limited to, various alkyl carbonates such as cyclic carbonates (e.g., ethylene Carbonate (EC), propylene Carbonate (PC), butylene Carbonate (BC), fluoroethylene carbonate (FEC)), linear carbonates (e.g., dimethyl carbonate (D)MC), diethyl carbonate (DEC), methyl ethyl carbonate (EMC)), aliphatic carboxylic acid esters (e.g., methyl formate, methyl acetate, methyl propionate), gamma-lactones (e.g., gamma-butyrolactone, gamma-valerolactone), chain structural ethers (e.g., 1, 2-dimethoxyethane, 1-2-diethoxyethane, ethoxymethoxyethane), cyclic ethers (e.g., tetrahydrofuran, 2-methyltetrahydrofuran, 1, 3-dioxolane), sulfur-containing compounds (e.g., sulfolane), and combinations thereof.
In various aspects, the separator 26 can be a microporous polymer separator. The microporous polymer separator may comprise, for example, a polyolefin. The polyolefin may be a homopolymer (derived from a single monomer component) or a heteropolymer (derived from more than one monomer component), which may be linear or branched. If the heteropolymer is derived from two monomer components, the polyolefin may take any arrangement of copolymer chains, including those of block copolymers or random copolymers. Similarly, if the polyolefin is a heteropolymer derived from more than two monomer components, it may likewise be a block copolymer or a random copolymer. In certain aspects, the polyolefin may be Polyethylene (PE), polypropylene (PP), or a blend of Polyethylene (PE) and polypropylene (PP), or a multi-layer structured porous film of Polyethylene (PE) and/or polypropylene (PP). Commercially available polyolefin porous separator membranes 26 include gel (r) ® 2500 (Single layer Polypropylene separator) and GELGARD ® 2320 (three layers of polypropylene/polyethylene/polypropylene separators) available from Celgard LLC.
When separator 26 is a microporous polymeric separator, it may be a single layer or a multi-layer laminate, which may be made by dry or wet processes. For example, in some cases, a single layer of polyolefin may form the entire separator 26. In other aspects, the separator 26 may be a fibrous membrane having a plurality of holes extending between opposing surfaces, and may have an average thickness of less than millimeters, for example. However, as another example, multiple discrete layers of similar or dissimilar polyolefins may be assembled to form microporous polymer separator 26. The separator 26 may also include other polymers besides polyolefins, such as, but not limited to, polyethylene terephthalate (PET), polyvinylidene fluoride (PVdF), polyamides, polyimides, poly (amide-imide) copolymers, polyetherimides, and/or cellulose, or any other material suitable for producing the desired porous structure. The polyolefin layer and any other optional polymer layers may further be included as fibrous layers in the separator 26 to help provide the separator 26 with suitable structural and porosity characteristics.
Various conventionally available polymers and commercial products for forming the separator 26 are contemplated, as well as a number of manufacturing methods that may be used to prepare such microporous polymer separators 26. In each case, the separator 26 can have an average thickness of greater than or equal to about 1 μm to less than or equal to about 50 μm, and in some cases, optionally greater than or equal to about 1 μm to less than or equal to about 20 μm. The separator 26 can have an average thickness of greater than or equal to 1 μm to less than or equal to 50 μm, and in some cases, optionally greater than or equal to 1 μm to less than or equal to 20 μm.
In each variation, the separator 26 may also include one or more ceramic materials and/or one or more heat resistant materials. For example, the separator 26 may also be mixed with one or more ceramic materials and/or one or more heat resistant materials, or one or more surfaces of the separator 26 may be coated with one or more ceramic materials and/or one or more heat resistant materials. The one or more ceramic materials may include, for example, alumina (Al 2 O 3 ) Silicon dioxide (SiO) 2 ) Etc. The heat resistant material may include, for example, nomex, aramid, and the like.
In various aspects, the porous separator 26 and/or the electrolyte 30 disposed in the porous separator 26 as shown in fig. 1 may be replaced with a solid electrolyte ("SSE") layer (not shown) and/or a semi-solid electrolyte (e.g., gel) layer that serve as both electrolyte and separator. A solid electrolyte layer and/or a semi-solid electrolyte layer may be disposed between positive electrode 24 and negative electrode 22. The solid electrolyte layer and/or the semi-solid electrolyte layer facilitate transfer of lithium ions while mechanically isolating and providing electrical insulation between the negative electrode 22 and the positive electrode 24. As non-limiting examples, the solid electrolyte layer and/or the semi-solid electrolyte layer may include a variety of solid electrolyte particles, such as LiTi 2 (PO 4 ) 3 、LiGe 2 (PO 4 ) 3 、Li 7 La 3 Zr 2 O 12 、Li 3 xLa 2/3 -xTiO 3 、Li 3 PO 4 、Li 3 N、Li 4 GeS 4 、Li 10 GeP 2 S 12 、Li 2 S-P 2 S 5 、Li 6 PS 5 Cl、Li 6 PS 5 Br、Li 6 PS 5 I、Li 3 OCl、Li 2.99 Ba 0.005 ClO or a combination thereof.
Positive electrode 24 may be formed of a lithium-based active material that is capable of undergoing plating and stripping of lithium while functioning as a positive electrode terminal of a lithium ion battery. Positive electrode 24 may be defined by a plurality of particles of electroactive material (not shown). Such positive electrode electroactive material particles may be disposed in one or more layers so as to define the three-dimensional structure of positive electrode 24. Electrolyte 30 may be introduced, for example, after battery assembly and contained within pores (not shown) of positive electrode 24. In certain variations, positive electrode 24 may comprise a plurality of solid electrolyte particles (not shown). In each case, positive electrode 24 can have an average thickness of greater than or equal to about 1 μm to less than or equal to about 500 μm, and in certain aspects, optionally greater than or equal to about 10 μm to less than or equal to about 200 μm. Positive electrode 24 can have an average thickness of greater than or equal to 1 μm to less than or equal to 500 μm, and in certain aspects, optionally greater than or equal to 10 μm to less than or equal to 200 μm.
One exemplary common class of known materials that may be used to form positive electrode 24 is layered lithium transition metal oxides. For example, in certain aspects, positive electrode 24 may comprise one or more materials having a spinel structure, such as lithium manganese oxide (Li (1+x) Mn 2 O 4 Wherein x is more than or equal to 0.1 and less than or equal to 1) (LMO), lithium manganese nickel oxide (LiMn) (2-x) Ni x O 4 Where 0.ltoreq.x.ltoreq.0.5) (LNMO) (e.g.LiMn 1.5 Ni 0.5 O 4 ) The method comprises the steps of carrying out a first treatment on the surface of the One or more materials having a layered structure, e.g. lithium cobalt oxide (LiCoO) 2 ) Lithium and lithiumNickel manganese cobalt oxide (Li (Ni) x Mn y Co z )O 2 Where 0.ltoreq.x.ltoreq.1, 0.ltoreq.y.ltoreq.1, 0.ltoreq.z.ltoreq.1, and x+y+z=1) (e.g. LiMn 0.33 Ni 0.33 Co 0.33 O 2 ) (NMC) or lithium nickel cobalt metal oxide (LiNi (1-x-y) Co x M y O 2 Wherein 0 < x < 0.2, y < 0.2, and M can be Al, mg, ti, etc.); or lithium iron polyanion oxides having an olivine structure, e.g. lithium iron phosphate (LiFePO) 4 ) (LFP), lithium manganese iron phosphate (LiMn) 2-x Fe x PO 4 Wherein 0 < x < 0.3) (LFMP), or lithium iron fluorophosphate (Li) 2 FePO 4 F) A. The invention relates to a method for producing a fibre-reinforced plastic composite In various aspects, positive electrode 24 may comprise one or more electroactive materials selected from the group consisting of: NCM 111, NCM 532, NCM 622, NCM 811, NCMA, LFP, LMO, LFMP, LLC, and combinations thereof.
In certain variations, one or more positive electrode electroactive materials in positive electrode 24 may optionally be mixed with an electronically conductive material that provides an electronically conductive path and/or at least one polymeric binder material that improves the structural integrity of electrode 24. For example, one or more positive electrode electroactive materials in positive electrode 24 may optionally be mixed (e.g., slurry cast) with a binder such as polyimide, polyamide acid, polyamide, polysulfone, polyvinylidene fluoride (PVdF), polytetrafluoroethylene (PTFE), ethylene Propylene Diene Monomer (EPDM) or carboxymethyl cellulose (CMC), nitrile rubber (NBR), styrene-butadiene rubber (SBR), lithium polyacrylate (LiPAA), sodium polyacrylate (NaPAA), sodium alginate or lithium alginate. The conductive material may comprise a carbon-based material, powdered nickel or other metal particles, or a conductive polymer. The carbon-based material may include, for example, graphite, acetylene black (e.g., KETJEN TM Black or DENKA TM Black), carbon fibers and particles of nanotubes, graphene, etc. Examples of the conductive polymer include polyaniline, polythiophene, polyacetylene, polypyrrole, and the like. In certain aspects, mixtures of conductive materials may be used.
Positive electrode 24 can comprise greater than or equal to about 5 wt% to less than or equal to about 99 wt%, optionally greater than or equal to about 10 wt% to less than or equal to about 99 wt%, and in certain variations, greater than or equal to about 50 wt% to less than or equal to about 98 wt% of one or more positive electrode electroactive materials; greater than or equal to 0 wt% to less than or equal to about 40 wt%, and in certain aspects, optionally greater than or equal to about 1 wt% to less than or equal to about 20 wt% electronically conductive material; and greater than or equal to 0 wt% to less than or equal to about 40 wt%, and in certain aspects, optionally greater than or equal to about 1 wt% to less than or equal to about 20 wt% of at least one polymeric binder.
Positive electrode 24 can comprise greater than or equal to 5 wt% to less than or equal to 99 wt%, optionally greater than or equal to 10 wt% to less than or equal to 99 wt%, and in certain variations, greater than or equal to 50 wt% to less than or equal to 98 wt% of one or more positive electrode electroactive materials; greater than or equal to 0 wt% to less than or equal to 40 wt%, and in certain aspects, optionally greater than or equal to 1 wt% to less than or equal to 20 wt% electronically conductive material; and greater than or equal to 0 wt% to less than or equal to 40 wt%, and in certain aspects, optionally greater than or equal to 1 wt% to less than or equal to 20 wt% of at least one polymeric binder.
The negative electrode 22 may be formed of a lithium host material capable of functioning as a negative electrode terminal of a lithium ion battery. For example, in various aspects, the negative electrode 22 may be defined by lithium, e.g., in certain variations, the negative electrode 22 may be defined by lithium metal foil. In various aspects, as shown in fig. 2, at least one surface 23 of the lithium metal negative electrode 22 may have a predetermined surface design including a plurality of dimples 60. For example, the plurality of dimples 60 can occupy greater than or equal to about 20% to less than or equal to about 90%, and in certain aspects, optionally greater than or equal to about 40% to less than or equal to about 60%, of the total surface area of the at least one surface 23 of the lithium metal negative electrode 22. In certain variations, the plurality of dimples 60 may occupy greater than or equal to 20% to less than or equal to 90%, and in certain aspects, optionally greater than or equal to 40% to less than or equal to 60%, of the total surface area of the at least one surface 23 of the lithium metal negative electrode 22.
The dimples 60 can take a variety of configurations. Generally, the dimples 60 can have a circular cross-sectional shape, such as circular, oval, etc. In addition, the side of the recess 60 opposite the negative electrode 22 (e.g., the exposed surface 25) may be concave. In some variations, the dimples 60 may be dispersed in a substantially continuous or uniform fashion. In other variations, the pits 60 may be dispersed so as to define a selected pattern. In still other variations, the pits 60 may be randomly dispersed. However, in each variation, the dimples 60 can have an average lateral dimension 27 (e.g., an average diameter of the plurality of dimples) of greater than or equal to about 100 nm to less than or equal to about 100 μm, and in certain aspects, optionally greater than or equal to about 1 μm to less than or equal to about 60 μm; and greater than or equal to about 100 nm to less than or equal to about 50 μm, and in certain aspects, optionally greater than or equal to about 500 nm to less than or equal to about 10 μm of average depth 29 (e.g., average depth of the plurality of pits). In certain variations, the dimples 60 can have an average lateral dimension 27 (e.g., an average diameter of a plurality of dimples) of greater than or equal to 100 nm to less than or equal to 100 μm, and in certain aspects, optionally greater than or equal to 1 μm to less than or equal to 60 μm; and greater than or equal to 100 nm to less than or equal to 50 μm, and in certain aspects, optionally greater than or equal to 500 nm to less than or equal to 10 μm average depth 29 (e.g., average depth of the plurality of pits).
Pits 60 have a lower energy surface than flat (i.e., non-pitted) areas of the surface of the lithium metal film (e.g., exposed surface 25). In this manner, the dimples 60 provide preferential sites for lithium nucleation during lithium deposition (i.e., during charging of the battery 20) and/or growth during operation of the battery 20, and help to inhibit or reduce the formation of relatively large lithium metal dendrites. That is, the pits 60 promote the formation and/or growth of more diffuse lithium metal dendrites such that the formed lithium metal dendrites are smaller (as compared to a flat surface) and generally fewer larger dendrites are formed thereon.
In various aspects, the present disclosure provides methods for forming a lithium metal negative electrode having a surface design that preferentially nucleates lithium during battery operation, such as the lithium metal negative electrode shown in fig. 1 and 2. For example, FIG. 3 shows a method for formingAn exemplary method 300 of a negative electrode having a surface design that preferentially nucleates lithium during battery operation. In various aspects, the method 300 is an in situ electrochemical method that includes stripping 330 lithium ions from one or more lithium metal negative electrodes, for example, after battery fabrication by applying a current having a value greater than or equal to about 0.1 mA/cm 2 To less than or equal to about 10 mA/cm 2 And, in certain aspects, optionally greater than or equal to about 1 mA/cm 2 To less than or equal to about 8 mA/cm 2 Is used for the current density of the battery. In certain variations, the applied current density may be greater than or equal to 0.1 mA/cm 2 To less than or equal to 10 mA/cm 2 And, in certain aspects, optionally greater than or equal to 1 mA/cm 2 To less than or equal to 8 mA/cm 2 . By way of comparison only, for standard formation, the current density is typically greater than or equal to about 0.2 mA/cm 2 To less than or equal to about 0.5 mA/cm 2 . In the present case, the (higher) current density may be applied for a time period of greater than or equal to about 1 second to less than or equal to about 20 minutes, and in some aspects, optionally greater than or equal to about 30 seconds to less than or equal to about 10 minutes (e.g., a peel time). In certain variations, the (higher) current density may be applied for a time (e.g., peel time) of greater than or equal to 1 second to less than or equal to 20 minutes, and in certain aspects, optionally greater than or equal to 30 seconds to less than or equal to 10 minutes. When lithium is removed (i.e., stripped) from the lithium metal anode, pits are formed in the lithium metal negative electrode. One or more current densities and times are selected to control the number and size of the pits.
In certain variations, the method 300 may include assembling 320 a battery cell including one or more lithium metal negative electrodes. In still further variations, the method 300 may include refining 310 the microstructure of one or more lithium metal negative electrodes. For example, in some variations, refining 310 includes increasing the number of grain boundaries where preferential dishing occurs during exfoliation 330. As will be appreciated by those skilled in the art, grain boundary (heterogeneous) nucleation requires less energy than homogeneous nucleation. The microstructure of one or more lithium metal negative electrodes 310 may be refined 310 using a particular refinement process. For example, in various aspects, the grain refinement process may include cold rolling, multi-pass rolling, cross rolling, and the like. In yet a further variation, the method 300 may further include applying 340 a standard formation protocol to the battery after the lithium stripping 330. In certain variations, the standard formation scheme may include charging and discharging the battery one or more times at a relatively slow rate (e.g., C/20 or C/10).
The in situ electrochemical process 300 including stripping 330 and optional assembly 320 and/or refinement 310 can be readily integrated into existing negative electrode design and formation processes, including, by way of example only, lithium metal mesh anodes. Fig. 4A is a microscopic image of a lithium metal negative electrode 400 having a predetermined surface design defined by a plurality of dimples 410, for example, prepared using the method 300 shown in fig. 3. Fig. 4B is a microscopic image of a lithium metal negative electrode 450 having a predetermined surface design defined by a plurality of dimples 460 prepared, for example, using the method 300 shown in fig. 3. The lithium metal negative electrode 400 is at about 4.5 mA/cm 2 For about 5 minutes, while the lithium metal negative electrode 450 is at about 4.5 mA/cm 2 The lower treatment was carried out for about 2 minutes. By way of comparison only, fig. 4C is a microscopic image of an untreated lithium metal negative electrode 490.
Fig. 5 illustrates another exemplary method for forming a negative electrode having a surface design that preferentially nucleates lithium during battery operation. In various aspects, the method is a mechanical method comprising introducing a plurality of dimples 526 on one or more surfaces of the lithium metal negative electrode 522, for example, using a rolling process, wherein the rolling process comprises contacting a roller 500 having a defined shape 502 with one or more surfaces 512 of the lithium metal negative electrode 522 to form the dimples 526, as illustrated. As illustrated, lithium metal negative electrode 522 may be disposed on or near current collector 532, and contacting may include, for example, moving or rolling a roller along lithium metal negative electrode 522. The roller 500 may be configured to apply a pressure of greater than or equal to about 2 MPa to less than or equal to about 50 MPa. Although a circular shape is shown in fig. 5, those skilled in the art will appreciate that in various instances, the defined shape 502 may take on various configurations and spacings to form pits having various shapes and sizes, and various patterns on the surface of the lithium metal negative electrode 522. Although not shown, in certain variations, the method may further comprise assembling the battery and incorporating therein a lithium metal negative electrode 522 comprising a plurality of dimples 526. Furthermore, as in the case of the method 400 detailed above, the mechanical method may include refining the microstructure of the lithium metal negative electrode 522 prior to the mechanical or rolling process and/or applying a standard formation protocol to the battery after battery assembly. Still further, in certain variations, the method may include disposing lithium metal negative electrode 522 on or near one or more surfaces of current collector 532.
Fig. 6 illustrates another exemplary method 600 for forming a negative electrode having a surface design that preferentially nucleates lithium during battery operation. In various aspects, the method 600 is a chemical method that includes, for example, contacting 620 one or more surfaces of a lithium metal negative electrode with a chemical etchant selected to introduce pits into the one or more surfaces of the lithium metal negative electrode, and more particularly, at grain boundaries. The chemical etchant may be selected from: diethyl ketone, dodecylbenzene sulfonic acid (DBSA), rosin acid, nitric acid, acetic acid, hydrofluoric acid, sulfuric acid, hydrochloric acid, and combinations thereof.
In certain variations, contacting 620 one or more surfaces of the lithium metal negative electrode with the chemical etchant may include a bath process in which the lithium metal negative electrode is immersed in a solution comprising the chemical etchant. The solution may further comprise an anhydrous alcohol (e.g., ethanol, methanol, isopropanol, etc.). The solution may comprise greater than 0 wt% to less than or equal to about 30 wt%, optionally greater than 0 wt% to less than or equal to about 10 wt%, and in certain aspects, optionally greater than 0 wt% to less than or equal to about 5 wt% chemical etchant. The solution may comprise greater than 0 wt% to less than or equal to 30 wt%, optionally greater than 0 wt% to less than or equal to 10 wt%, and in some aspects optionally greater than 0 wt% to less than or equal to 5 wt% chemical etchant.
In other variations, contacting 620 one or more surfaces of the lithium metal negative electrode with the chemical etchant may include spraying the chemical etchant or a solution containing the chemical etchant onto one or more surfaces of the lithium metal negative electrode. The solution may comprise greater than 0 wt% to less than or equal to about 30 wt%, optionally greater than 0 wt% to less than or equal to about 10 wt%, and in certain aspects, optionally greater than 0 wt% to less than or equal to about 5 wt% chemical etchant. The solution may comprise greater than 0 wt% to less than or equal to 30 wt%, optionally greater than 0 wt% to less than or equal to 10 wt%, and in certain aspects, optionally greater than 0 wt% to less than or equal to 5 wt% chemical etchant.
In each case, the chemical etchant may be maintained in contact with one or more surfaces of the lithium metal negative electrode for a period of time of greater than or equal to about 2 seconds to less than or equal to about 10 minutes, and in certain aspects, optionally greater than or equal to about 5 seconds to less than or equal to about 5 minutes. In certain variations, the chemical etchant may be maintained in contact with one or more surfaces of the lithium metal negative electrode for a period of time greater than or equal to 2 seconds to less than or equal to 10 minutes, and in certain aspects, optionally greater than or equal to 5 seconds to less than or equal to 5 minutes.
In each case, the contacting 620 of one or more surfaces of the lithium metal negative electrode may occur at a temperature of greater than or equal to about-40 ℃ to less than or equal to about 60 ℃, and in certain aspects, optionally, greater than or equal to-40 ℃ to less than or equal to 60 ℃.
In various aspects, similar to method 400, method 600 may further include refining 610 the microstructure of the lithium metal negative electrode prior to contacting 620 the lithium metal negative electrode with the chemical etchant. Further, in certain variations, the method 600 may include assembling 630 a battery and incorporating therein a lithium metal negative electrode that includes a plurality of pits formed by a chemical process. Still further, in some variations, similar to method 400, method 600 may include applying 640 a standard formation scheme to the battery after the battery is assembled. Although not shown, one of ordinary skill in the art will recognize that in certain variations, the method 600 may include rinsing the lithium metal negative electrode after the contacting 620 to remove excess material, such as excess chemical etchant.
Certain features of the present technology are further illustrated in the following non-limiting examples.
Example 1
Embodiments battery cells may be prepared according to various aspects of the present disclosure.
For example, an embodiment battery cell 610 may include a lithium metal negative electrode having a predetermined surface design defined by a plurality of dimples, such as the lithium metal electrode 22 shown in fig. 1 and 2. The comparative battery 620 may include an untreated lithium metal negative electrode.
Fig. 7 is a graph showing the discharge capacity retention (%) of the battery cell 710 of the embodiment compared to the comparative battery cell 720, wherein the x-axis 700 represents the number of cycles and the y-axis 702 represents the discharge capacity retention (%). As shown, the example battery cell 710 has improved cell performance, including both cell discharge capacity and cell cycling stability, as evidenced by the flattening of the curve with high values as a function of cycle number.
The foregoing description of the embodiments has been presented for purposes of illustration and description. It is not intended to be exhaustive or to limit the disclosure. The individual elements or features of a particular embodiment are generally not limited to that particular embodiment, but, where applicable, are interchangeable and can be used in a selected embodiment, even if not specifically shown or described. As such, may be varied in many ways. Such variations are not to be regarded as a departure from the disclosure, and all such modifications are intended to be included within the scope of the disclosure.

Claims (10)

1. A method of forming an electrode for use in an electrochemical cell for circulating lithium ions, the method comprising:
forming a plurality of pits on one or more surfaces of a precursor electrochemical layer to form an electrochemical layer, the electrochemical layer comprising lithium metal, and pits of the plurality of pits having an average lateral dimension of greater than or equal to about 100 nm to less than or equal to about 100 μm, and a depth of greater than or equal to about 100 nm to less than or equal to about 50 μm, wherein the electrode comprises the electrochemical layer.
2. The method of claim 1, whereinForming pits in the plurality of pits in situ by applying a current to the precursor electrochemical layer, wherein the current has a current density of greater than or equal to about 0.1 mA/cm 2 To less than or equal to about 10 mA/cm 2 And applying the current density for a time of greater than or equal to about 1 second to less than or equal to about 20 minutes.
3. The method of claim 1, the forming comprising:
a roller having a plurality of shapes defined thereon is moved along one or more surfaces of the precursor electrochemical layer.
4. The method of claim 1, wherein the forming comprises:
contacting one or more surfaces of the precursor electrochemical layer with a chemical etchant, wherein the precursor electrochemical layer is contacted with the chemical etchant for a time period of greater than or equal to about 2 seconds to less than or equal to about 10 minutes.
5. The method of claim 4, wherein the chemical etchant is selected from the group consisting of: diethyl ketone, dodecylbenzene sulfonic acid (DBSA), rosin acid, nitric acid, acetic acid, hydrofluoric acid, sulfuric acid, hydrochloric acid, and combinations thereof.
6. The method of claim 4, wherein the contacting comprises one of:
immersing the precursor electrochemical layer in a bath comprising the chemical etchant; and is also provided with
One or more surfaces of the precursor electrochemical layer are sprayed with a solution comprising the chemical etchant.
7. The method of claim 1, the method further comprising:
the precursor is subjected to a grain refinement process electrochemically (layer).
8. The electrode of claim 1, wherein a dimple of the plurality of dimples occupies greater than or equal to about 20% to less than or equal to about 90% of the total surface area of the one or more surfaces.
9. The negative electrode of claim 1, wherein the dimples of the plurality of dimples are randomly distributed over one or more surfaces of the electrochemical layer.
10. The electrode of claim 1, wherein the pits of the plurality of pits are dispersed at a uniform density on one or more surfaces of the electrochemical layer.
CN202211269467.7A 2022-02-16 2022-10-17 Lithium metal anode for electrochemical cells and method for making same Pending CN116646474A (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US17/673,437 US20230261173A1 (en) 2022-02-16 2022-02-16 Lithium metal anodes for use in electrochemical cell and methods of making the same
US17/673437 2022-02-16

Publications (1)

Publication Number Publication Date
CN116646474A true CN116646474A (en) 2023-08-25

Family

ID=87430777

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202211269467.7A Pending CN116646474A (en) 2022-02-16 2022-10-17 Lithium metal anode for electrochemical cells and method for making same

Country Status (3)

Country Link
US (1) US20230261173A1 (en)
CN (1) CN116646474A (en)
DE (1) DE102022126320A1 (en)

Also Published As

Publication number Publication date
US20230261173A1 (en) 2023-08-17
DE102022126320A1 (en) 2023-08-17

Similar Documents

Publication Publication Date Title
US11417888B2 (en) Electrode additives and coatings for minimizing cathode transition metal dissolution
CN115241456A (en) Current collector with surface structure for controlling formation of solid electrolyte interface layer
US20220181629A1 (en) Elastic binding polymers for electrochemical cells
US20230006201A1 (en) Over-lithiated cathode materials and methods of forming the same
CN117174496A (en) Electrolyte additives for capacitor auxiliary batteries
US20230261173A1 (en) Lithium metal anodes for use in electrochemical cell and methods of making the same
US20240047673A1 (en) Nitrate salt cathode additives and methods of using and forming the same
US11799083B2 (en) Lithiation additive for a positive electrode
US20230246295A1 (en) Coated separators for electrochemical cells and methods of forming the same
US20230411614A1 (en) Electrolyte additive for nickel-rich cathodes and silicon-containing anodes
US20230335753A1 (en) Patterned current collector for anodeless electrochemical battery cells
US20240170720A1 (en) Electrolytes for electrochemical cells that cycle lithium ions
US20240047653A1 (en) Protective particle coatings for electroactive material particles and methods of forming the same
US20230102190A1 (en) Negative electroactive materials and methods of forming the same
US20240072242A1 (en) Electroactive materials for electrochemical cells and methods of forming the same
US20240038962A1 (en) Pre-lithiating porous layer for electrochemical cell and methods of forming the same
US20230361311A1 (en) Current collectors for electrochemical cells that cycle lithium ions
US20240079649A1 (en) Electrolytes for electrochemical cells that cycle lithium ions
US20240030552A1 (en) Protective layers separating electroactive materials and binder materials in electrode and methods of forming the same
US20230369568A1 (en) Lithium-containing particle coatings for positive electroactive materials
US20220102704A1 (en) Electroactive particles having electronically conductive coatings
CN116960279A (en) Protective layer for lithium metal electrode and method of forming the same
CN117276469A (en) Electrode with alternating layered structure
CN116779780A (en) Lithium protective coating for lithium-sulfur battery and method of forming the same
CN116504924A (en) Protective coating for lithium metal electrode and method of forming the same

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination